Common philosophical opinion of suicide since modernization reflected a spread in cultural beliefs of western societies that suicide is immoral and unethical. One popular argument is that many of the reasons for committing suicide – such as depression, emotional pain, or economic hardship – are transitory and can be ameliorated by therapy and through making changes to some aspects of one's life. A common adage in the discourse surrounding suicide prevention sums up this view: "Suicide is a permanent solution to a temporary problem." However, the argument against this is that while emotional pain may seem transitory to most people, and in many cases it is, in other cases it may be extremely difficult or even impossible to resolve, even through counseling or lifestyle change, depending upon the severity of the affliction and the person's ability to cope with their pain. Examples of this are incurable disease or lifelong mental illness.[1]

The French Algerianabsurdist philosopher Albert Camus saw the goal of absurdism in establishing whether suicide is a necessary response to a world which appears to be mute both on the question of God's existence (and thus what such an existence might answer) and for our search for meaning and purpose in the world. For Camus, suicide was the rejection of freedom. He thinks that fleeing from the absurdity of reality into illusions, religion, or death is not the way out. Instead of fleeing the absurd meaninglessness of life, we should embrace life passionately.

Existentialist Sartre describes the position of Meursault, the protagonist of Camus' L'Étranger who is condemned to death, in the following way:

The absurd man will not commit suicide; he wants to live, without relinquishing any of his certainty, without a future, without hope, without illusions ... and without resignation either. He stares at death with passionate attention and this fascination liberates him. He experiences the "divine irresponsibility" of the condemned man.[2]

G. K. Chesterton calls suicide "the ultimate and absolute evil, the refusal to take an interest in existence". He argues that a person who kills himself, as far as he is concerned, destroys the entire world (apparently exactly repeating Maimonides' view).

John Stuart Mill argued, in his influential essay "On Liberty", that since the sine qua non of liberty is the power of the individual to make choices, any choice that one might make that would deprive one of the ability to make further choices should be prevented. Thus, for Mill, selling oneself into slavery or killing oneself should be prevented in order to avoid precluding the ability to make further choices. Concerning these matters, Mill writes in "On Liberty"

Not only persons are not held to engagements which violate the rights of third parties, but it is sometimes considered a sufficient reason for releasing them from an engagement, that it is injurious to themselves. In this and most other civilized countries, for example, an engagement by which a person should sell himself, or allow himself to be sold, as a slave, would be null and void; neither enforced by law nor by opinion. The ground for thus limiting his power of voluntarily disposing of his own lot in life, is apparent, and is very clearly seen in this extreme case. The reason for not interfering, unless for the sake of others, with a person's voluntary acts, is consideration for his liberty. His voluntary choice is evidence that what he so chooses is desirable, or at the least endurable, to him, and his good is on the whole best provided for by allowing him to take his own means of pursuing it. But by selling himself for a slave, he abdicates his liberty; he forgoes any future use of it, beyond that single act. He therefore defeats, in his own case, the very purpose which is the justification of allowing him to dispose of himself. He is no longer free; but is thenceforth in a position which has no longer the presumption in its favour, that would be afforded by his voluntarily remaining in it. The principle of freedom cannot require that he should be free not to be free. It is not freedom, to be allowed to alienate his freedom.

Yet at the same time, Mill believes the individual to be the best guardian of their own interests. He uses the example of a man about to cross a broken bridge: we can forcibly stop that person and warn him of the danger, but ultimately should not prevent him from crossing the bridge—for only he knows the worth of his life balanced against the danger of crossing the bridge.

Immanuel Kant argues against suicide in Fundamental Principles of The Metaphysic of Morals. In accordance with the second formulation of his categorical imperative, Kant argues that, "He who contemplates suicide should ask himself whether his action can be consistent with the idea of humanity as an end in itself." Kant's theory looks at the act only, and not at its outcomes and consequences, and claims that one is ethically required to consider whether one would be willing to universalise the act: to claim everyone should behave that way. Kant argues that choosing to commit suicide entails considering oneself as a means to an end, which he rejects: a person, he says, must not be used "merely as means, but must in all actions always be considered as an end in himself." Therefore, it is unethical to commit suicide to satisfy oneself.

Hobbes and Locke reject the right of individuals to take their own life. Hobbes claims in his Leviathan that natural law forbids every man "to do, that which is destructive of his life, or take away the means of preserving the same." Breaking this natural law is irrational and immoral. Hobbes also states that it is intuitively rational for men to want felicity and to fear death most.

Japan has a form of suicide called seppuku, which is considered an honorable way to redeem oneself for transgressions or personal defeats. It was widely accepted in the days of the Samurai and even before that. It was generally seen as a right only permitted to the samurai class; civilian criminals would thus not have this 'honor' and be executed. This reflects a view of suicide as brave and correct rather than cowardly and wrong.[citation needed]

Utilitarianism can be used as a justification for, or an argument against, suicide. Though the death of a depressed person ends their suffering, the person's family and friends may grieve.[citation needed]

David Hume left an essay on suicide to be published after his death.[3] Most of it is concerned with the claim that suicide is an affront to God. Hume argues that suicide is no more a rebellion against God than is saving the life of someone who would otherwise die, or changing the position of anything in one's surroundings. He spends much less time dismissing arguments that it is an affront to one's duty to others or to oneself. Hume claims that suicide can be compared to retiring from society and becoming a total recluse, which is not normally considered to be immoral, although the comparison would not seem to justify a suicide that leaves in its wake children or dependents who are thereby rendered vulnerable. As for duty to self, Hume takes it to be obvious that there can be times when suicide is desirable, though he also thinks it ridiculous that anyone would consider suicide unless they first considered every other option.

Those who support the right to die argue that suicide is acceptable under certain circumstances, such as incurable disease and old age. The idea is that although life is, in general, good, people who face irreversible suffering should not be forced to continue suffering.

Suicide is justified when man's life, owing to circumstances outside of a person's control, is no longer possible; an example might be a person with a painful terminal illness, or a prisoner in a concentration camp who sees no chance of escape. In cases such as these, suicide is not necessarily a philosophic rejection of life or of reality. On the contrary, it may very well be their tragic reaffirmation. Self-destruction in such contexts may amount to the tortured cry: "Man's life means so much to me that I will not settle for anything less. I will not accept a living death as a substitute."

Bioethicist Jacob Appel has criticized "arbitrary" ethical systems that allow patients to refuse care when they are physically ill, while denying the mentally ill the right to suicide.[4][5]

There are arguments in favor of allowing an individual to choose between life and suicide. Those in favor of suicide as a personal choice reject the thought that suicide is always or usually irrational, but is instead a solution to real problems; a line of last resort that can legitimately be taken when the alternative is considered worse. They believe that no being should be made to suffer unnecessarily, and suicide provides an escape from suffering.

Herodotus wrote: "When life is so burdensome, death has become for man a sought-after refuge". Schopenhauer affirmed: "They tell us that suicide is the greatest act of cowardice... that suicide is wrong; when it is quite obvious that there is nothing in the world to which every man has a more unassailable title than to his own life and person."

Schopenhauer's main work, The World as Will and Representation, occasionally uses the act in its examples. He denied that suicide was immoral and saw it as one's right to take one's life. In an allegory, he compared ending one's life, when subject to great suffering, to waking up from sleep when experiencing a terrible nightmare. However, most suicides were seen as an act of the will, as it takes place when one denies life's pains, and is thus different from ascetic renunciation of the will, which denies life's pleasures.

According to Schopenhauer, moral freedom — the highest ethical aim — is to be obtained only by a denial of the will to live. Far from being a denial, suicide is an emphatic assertion of this will. For it is in fleeing from the pleasures, not from the sufferings of life, that this denial consists. When a man destroys his existence as an individual, he is not by any means destroying his will to live. On the contrary, he would like to live if he could do so with satisfaction to himself; if he could assert his will against the power of circumstance; but circumstance is too strong for him. In short, Schopenhauer in no way advocated or supported suicide, he merely rejected the way it was viewed as a crime in his society.[citation needed]

Liberalism asserts that a person's life belongs only to them, and no other person has the right to force their own ideals that life must be lived. Rather, only the individual involved can make such a decision, and whatever decision they make should be respected.

Philosopher and psychiatrist Thomas Szasz goes further, arguing that suicide is the most basic right of all. If freedom is self-ownership—ownership over one's own life and body—then the right to end that life is the most basic of all. If others can force you to live, you do not own yourself and belong to them.[6]

Jean Améry, in his book On Suicide: a Discourse on Voluntary Death (originally published in German in 1976), provides a moving insight into the suicidal mind. He argues forcefully and almost romantically that suicide represents the ultimate freedom of humanity, justifying the act with phrases such as "we only arrive at ourselves in a freely chosen death" and lamenting "ridiculously everyday life and its alienation".[citation needed] Améry killed himself in 1978.

Philosophical thinking in the 19th and 20th century has led, in some cases, beyond thinking in terms of pro-choice, to the point that suicide is no longer a last resort, or even something that one must justify, but something that one must justify not doing. Many forms of existentialist thinking essentially begin with the premise that life is objectively meaningless, and proceed to the question of why one should not just kill oneself; they then answer this question by suggesting that the individual has the power to give personal meaning to life.

The Stoics accepted that suicide was permissible for the wise person in circumstances that might prevent them from living a virtuous life.[8]Plutarch held that accepting life under tyranny would have compromised Cato's self-consistency (constantia) as a Stoic and impaired his freedom to make the honorable moral choices.[9] Suicide could be justified if one fell victim to severe pain or disease,[8] but otherwise suicide would usually be seen as a rejection of one's social duty.[10]

Confucianism holds that failure to follow certain values is worse than death; hence, suicide can be morally permissible, and even praiseworthy, if it is done for the sake of those values. The Confucian emphasis on loyalty, self-sacrifice, and honour has tended to encourage altruistic suicide.[11]Confucius wrote, "For gentlemen of purpose and men of ren while it is inconceivable that they should seek to stay alive at the expense of ren, it may happen that they have to accept death in order to have ren accomplished."[12]Mencius wrote:[13]

Fish is what I want; bear's palm is also what I want. If I cannot have both, I would rather take bear's palm than fish. Life is what I want; yi is also what I want. If I cannot have both, I would rather take yi than life. On the one hand, though life is what I want, there is something I want more than life. That is why I do not cling to life at all cost. On the other hand, though death is what I loathe, there is something I loathe more than death. That is why there are dangers I do not avoid ... Yet there are ways of remaining alive and ways of avoiding death to which a person will not resort. In other words, there are things a person wants more than life and there are also things he or she loathes more than death.